This invention is directed to an ARL compound that exhibits acute vasodilator as well as antihypertensive properties and to a class of compounds structually related to the ARL compund that are acute vasodilator as well as antihypertensive properties and/or can be used as intermediates to produce such compounds. In the prior art, compositions were extracted from rabbit medulla and have been shown at high doses to provide antihypertensive activity and vasodepression activity (see Muirhead, E. E. et al., J. Lab. & Clin. Med. 56:167, 1960 and the other Muirhead et al. references in Proceedings of the Seminar on Hypertension, Supplement to Annals of Academy at Medicine, The Academy of Singapore, V.5, No. 3, July 1976, pp 36-44).
However, such prior compounds have been non-polar, low in potency and in many cases the results were not reproducible, i.e., activity seemed to disappear on a batch by batch basis.